Enormous activity has taken place in recent years, and resources expended, towards defining a broad range of near-term and future satellite communication (satcom) systems and services. These services, which may be provided or regional or global bases, accommodate both stationary and mobile users, and range in sophistication from one-way paging and messaging, to two-way high-quality voice. During recent years, activities have also included many filings with the FCC in order to receive approval to proceed with development, launch, and operations by the mid-to-late 1990's.